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Comment by dexen | Hacker News Reader

http://en.wikipedia.org/wiki/Plan_9_from_Bell_Labs follows the Unix philosophy. A lot of legacy has been shed. I can count 13 options to ls, 11 options to sed and just 5 to sed.

The standard Plan 9 shell, Rc, is described in mere ~500 lines of manpage, while Bash takes whooping ~5400 lines.

Oh, and there is no `dll hell' in P9 :-)

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> A lot of legacy has been shed.

An example I remember from the UNIX to Plan 9 command translation page[1]:

    UNIX                       Plan 9

    head                       sed 10q

[1]: http://www.plan9.bell-labs.com/wiki/plan9/unix_to_plan_9_com...

Looking at this list I can't really tell why this is supposed to be better. Shedding complexity ok - but getting rid of many shorthands that are there for a reason? It reminds me of how Java wanted to replace printf with a ridiculously complex string formatting system.

The point is that "head" on your system is not the same as "sed 10q". There are two different codebases. By default head shows the first 10 lines but you can change it with flags etc. Well why bother when you already have sed to do that?

  head -n 5         sed 5q

For most cases, head is not a shortcut. 10 is just a special case.

I agree with that change. I don't with many others.

Getting rid of good things would be bad, but is sed 10q really "ridiculously complex"?

No, but $home instead of ~ is, IMO.

Ah, fair enough. I really only meant to cite the one example - since I found it so striking when I first saw it. (It had never occurred to me to use sed for head that way.)

The thing is that ~ is special shell magic. $home is an environment variable, and is consistently expanded as such.

Although, to my eyes, the most plan9-y way of implementing a home directory would be to have '/home' as your home directory no matter what, and have it default to a bind from /usr/$username.

btw why /usr? I get it that in unix legacy it started as the users folder, but won't this be confusing as hell for all people that have come to know it as unix system resources? Why not /users?

Because that is what it's called on plan9.

I really like plan 9 conceptually, but what am I supposed to actually do with it? Here's a list of services I need to provide, can I do any of these with plan 9?

Email (smtp+ssl, pop3+ssl, imap+ssl, greylisting + spam and virus scanning, virtual accounts authenticating against some central source like ldap) central authentication (windows domain, kerberos domain, something along those lines that can authenticate windows clients) file servers (again, windows clients, using central authentication) web servers (just simple static file serving and proxying dynamic content to app servers) database server (no postgresql for plan 9 still) app servers (pretty much no languages support plan 9, so our custom web apps are a no go right?)

As far as I know, I can't do any of those things with plan 9. Am I mistaken? Is there something I am not thinking of that I could use it for? Do people only use it in their own private little plan 9 only networks? It doesn't make much sense to offer plan 9 as an alternative to unix-like systems if it can't do 99.9% of the things unix-like systems are used for.

> but what am I supposed to actually do with it?

Plan 9 is a research os that was made to explore the rigorous implementation of a few key ideas. You're missing the point if your criticism of it is that it doesn't run your favorite database.

If you like the ideas that Plan 9 implements you should apply them to you favorite big and nasty, full-of-compromises, gets-real-work-done OS.

For example, a key idea in Plan 9 is that all resources, from files and networks, to a processes runtime environment, to compute clusters should be represented as an entry in a single hierarchical namespace that is accessed with file semantics(read(),write()).

This is a really cool approach. It makes interacting with resources really easy. You can use any tools that manipulate files. It allows easy remote sharing and manipulation.

Want to use a printer on a different machine? Mount the printer and go. Want to write to a remote screen? Mount the framebuffer and go. Want to administer a running daemon? Mount the directory that represents it and starting messing around.

You can also create your own resources in this namespace. An example was a computing cluster with a file interface. Want to run a program on the cluster? Just mount the file an write your binary to it.

It is a neat approach and I would recommend you check it out.

I am not making a criticism, I am asking a question. I already know about plan 9, I don't need to "check it out". I would like to know how I can actually use it for something, rather than just play with it for a couple hours and go "yeah ok, that was cool".

It very much depends on what you want to do. But yes, you can certainly do things with Plan 9. Ruling out Plan 9 because it does run a certain language, or doesn't run Postgres, is like ruling out Linux because it can't run Microsoft Office. It is intended for a different purpose. Also note that Coraid use Plan 9 in a lot of their systems, to do real work (specifically SANs).

Edit: Also, Plan 9 has HTTP servers, CIFS support, central authentication (factotum), etc. I suggest you Google them.

I gave a list of things I want to do. The typical server stuff 99% of unix-like systems are used for. I am not ruling out plan 9, I am asking what it can be used for. Why do people keep insisting on deliberately misrepresenting a question as a criticism?

I know plan 9 has factotum, but "google it" sure doesn't help me find a way to use it to authenticate windows clients. Or authenticate anything other than plan 9 for that matter. Aquarela doesn't even claim to work, and it is actually much worse in practice than it claims to be. And it can't be part of a domain can it?

I'm not trying to be critical here, but when I ask "what can I actually do with plan 9?" I am genuinely interested in a serious answer. Stuff like "well there's an unsupported kinda buggy thing that doesn't actually do what you need anyways" is just a less honest way of saying "you can't use it for anything".

You can play with it. You can write little programs and compile them. You can poke around its everything is a file filesystem. Your question is like "what can I do with a slinkie?"

Even openbsd can do more than that! (are you even still involved with openbsd?). Seriously though, people keep acting like plan 9 is a practical alternative to a unix-like system, and I would love for that to be true. So, I am asking for someone to show me how I can use it that way. If those people are full of it, that's an ok answer. But it isn't my fault people are offering up the slinky as an alternative when someone complains their xbox 360 rrod'ed.

I don't think people are suggesting plan9 is a practical alternative. They're just saying it's worth studying and understanding. If people advocate using plan9, it's because understanding comes from experience.

I took dexen's original post to be suggesting it as a practical alternative. Reading it over again, it still looks like he is suggesting it as a practical alternative. Perhaps he was being sarcastic and I missed the point.

He's saying if you want to see what real unix looks like, look at plan9. There's nothing in his post to suggest real unix is useful. :)

As I said, Coraid uses it for SANs. The question you're asking is equivalent to "Windows can play games, why doesn't Linux have any games?" Some of the things you might do with Unix Plan 9 cannot do. However, the reverse is also true.

You seem to seem to be looking for "an alternative to Unix." If that is the case, Plan 9 probably isn't what you're looking for. It is, however, useful in ways that Unix is not. It probably won't replace your specific Unix needs, though it largely replaces mine. Hope that clears that up.

Except I asked the question in response to someone offering up plan 9 as though it were an alternative to modern unix-like systems. Taking the question out of context will inevitably make your response pointless. If someone said "windows crashes too much when I am playing games" and someone else said "linux never crashes" in response, then it would be perfectly reasonable to expect the linux guy to explain how to play games on linux.

Since plan 9 largely replaces your unixy needs, could you share with me what those needs are, so I can try to get a better idea of what I might be able to use it for. I am not looking for an alternative to unix, I am looking for any practical way I can put plan 9 to use, rather than just tinkering with it on an old spare machine for fun.

I think this is a more astute observation than people are giving you credit for.

UNIX grew to the complexity it has because it was meant to be used. Plan 9 is not used because it was not allowed to acquire useful constructs.

This parting ways with "the UNIX way" was necessary and complete in order for the system to become what it is today. Some things could be improved and made more proper and UNIXy, but for the most part it's an incredibly useful and functional system. The OP article is spot-on with this realization.

In other words, the ideal UNIX (for example, Plan 9) can't compete in the real world, because the concepts behind it (the UNIX way) don't actually compete in the real world. It's based on a set of very interesting, very elegant, and mostly false precepts.

>I am not making a criticism, I am asking a question. I already know about plan 9, I don't need to "check it out". I would like to know how I can actually use it for something, rather than just play with it for a couple hours and go "yeah ok, that was cool".

If you "know about it", then you would also now that you cannot use it for something like the things you mention. I cannot see how your questions are compatible with "knowing about it".

Even its developers doesn't use it now --although they have ported their favorite userland tools from it to other systems.

Have you tried reading my post? I said that as far as I am aware, you can't use it for any of those things, but that I could be mistaken. Ignoring what I said, to tell me what I said is stupid isn't productive or helpful.

> I am not making a criticism

I did not interpret your post as a criticism. Why do you think I did?

> I would like to know how I can actually use it for something

You can use it as a source of ideas for implementing operating system and network services. That may not be useful for you, but everyone is not like you. Others have found it useful to use directly(coraid).

I mainly think you did because of you saying you did: "You're missing the point if your criticism of it is that it doesn't run your favorite database."

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